Mary Doria Russell put it memorably (for me) in this quote, http://www.goodreads.com/quotes/417319-we-all-make-vows-jimmy-and-there-is-something-very http://ww

Mary Doria Russell put it memorably (for me) in this quote, http://www.goodreads.com/quotes/417319-we-all-make-vows-jimmy-and-there-is-something-very http://www.goodreads.com/quotes/417319-we-all-make-vows-jimm... It's longer, but here's one part. The speaker is explaining being married 4 times to 4 different men (each named George--the "same" person). "Every ten years or so, George and I have faced the fact that we have changed and we've had to decide if it makes sense to create a new marriage between these two new people. . . . Which is why vows are such a tricky business. Because nothing stays the same forever."